Better building could have lessened Joplin tornado damage, study says

A two-year long study from the National Institute of Standards and Technology (NIST) reveals that national standards for building construction could reduce damage from tornadoes. NIST swung into action a mere two days after the tornado, sending a team to extract information that could help in future storms.

The 2011 Joplin tornado is the deadliest on record. On May 22 of that year, the tornado’s seven mile path injured 1,000 people, killed 161, and damaged 8,000 buildings, resulting in property damage of $3 billion.

Property damage left by the Joplin tornado. From Kansas City District.

Better buildings could have saved lives

More than four in five of those deaths were caused by building collapses. People were unaware that the tornado was coming, or confused about emergency messages before the tornado arrived. Too many information sources and conflicting reports added to locals’ distrust and, as a result, they perceived the risk as minimal. Additionally, four out of five homes in the tornado zone lacked basements due to soil conditions, which led to greater damage.

Another recent study reached conclusions similar to the one conducted by NIST. The American Society of Civil Engineers found that most of the damage in Joplin was due to winds of 135 mph or less. Although the tornado reached speeds of 200 mph, the stronger winds did not cause the damage. The study suggested that the roof tiles used in hurricane zones would have been sufficient to avoid damage. Although NIST’s 492-page report lists many recommendations, it stresses that change can only come at the local level, from both government and businesses.

Changes have already started happening

In Joplin, new buildings must now use hurricane-clips on every rafter and truss. Public schools will now have reinforced safe rooms. The city also has temporary storm shelters, which were used by the Federal Emergency Management Agency at temporary housing sites.

According to NIST’s director of disaster and failure studies, Eric Letvin, current U.S. model building codes do not require protection against tornado hazards but do require protection from hurricanes, earthquakes, and floods. Mandating protection from tornadoes will also help minimize damage in future disasters.

Building new houses that are tornado-resistant is likely to add between 5 and 15 percent to the building cost, Letvin says. But compared to the property damage cost in the Joplin tornado, that seems like a small price to pay.